Index: Lib/test/test_normalization.py
===================================================================
--- Lib/test/test_normalization.py	(revision 77754)
+++ Lib/test/test_normalization.py	(working copy)
@@ -9,12 +9,9 @@
 TESTDATAFILE = "NormalizationTest" + os.extsep + "txt"
 TESTDATAURL = "http://www.unicode.org/Public/" + unidata_version + "/ucd/" + TESTDATAFILE
 
-if os.path.exists(TESTDATAFILE):
-    f = open(TESTDATAFILE)
-    l = f.readline()
-    f.close()
-    if not unidata_version in l:
-        os.unlink(TESTDATAFILE)
+def check_version(testfile):
+    hdr = testfile.readline()
+    return unidata_version in hdr
 
 class RangeError(Exception):
     pass
@@ -40,13 +37,14 @@
 
 class NormalizationTest(unittest.TestCase):
     def test_main(self):
+        part = None
         part1_data = {}
         # Hit the exception early
         try:
-            open_urlresource(TESTDATAURL)
+            testdata = open_urlresource(TESTDATAURL, check_version)
         except (IOError, HTTPException):
             self.skipTest("Could not retrieve " + TESTDATAURL)
-        for line in open_urlresource(TESTDATAURL):
+        for line in testdata:
             if '#' in line:
                 line = line.split('#')[0]
             line = line.strip()
Index: Lib/test/test_support.py
===================================================================
--- Lib/test/test_support.py	(revision 77754)
+++ Lib/test/test_support.py	(working copy)
@@ -438,7 +438,7 @@
     testcase.assertRaises(SyntaxError, compile, statement,
                           '<test string>', 'exec')
 
-def open_urlresource(url):
+def open_urlresource(url, check=lambda f: True):
     import urlparse, urllib2
 
     requires('urlfetch')
@@ -446,7 +446,12 @@
 
     fn = os.path.join(os.path.dirname(__file__), "data", filename)
     if os.path.exists(fn):
-        return open(fn)
+        f = open(fn)
+        if check(f):
+            f.seek(0)
+            return f
+        f.close()
+        unlink(fn)
 
     print >> get_original_stdout(), '\tfetching %s ...' % url
     f = urllib2.urlopen(url, timeout=15)